Boxing New Zealand's hopes of sending a fighter to the Olympics for the first time since Athens in 2004 are virtually on the ropes after their two leading contenders were beaten in the opening session of the Oceania qualifying tournament in Canberra last night.

Joe Blackbourn and Joseph Parker were both fated to draw top quality opponents in the quarterfinals of their weight divisions and saw their Olympic dreams dashed inside the Australian Institute of Sport ring, but David Light is still alive in the 91kg class after his Tongan adversary was disqualified for excessive use of the head.

Fa, who had won his two previous bouts against the 20-year-old Aucklander, dropped the first round 2-1 but came back strongly in the second to secure a decisive 3-point lead that he protected when the final three-minute joust ended in stalemate.

Wellingtonian Blackbourn also failed in his bid to succeed Soulan Pownceby as New Zealand's next boxing Olympian when his ambitions thwarted by Queensland's Jesse Ross who won their 75kg division clash 17-9.

A two-time Oceania champion, Blackbourn's preparations had been hampered by a broken finger sustained during a fight early last month, though it did not appear to impede his performance.

"He was never protecting his hands in any way. You would never have picked he had damage to his (right) hand," said Boxing New Zealand board member Keith Walker.

Ross was judged to have won each round and although Walker queried the margin, he had no quibble with the outcome.

"I don't think the score was reflective of the bout but the result was correct," he said.

"Joe was never in trouble, he was always in touch with the bout. It's just unfortunate."

Ross landed the telling blows in the second round, which he won 7-3. Blackbourn then needed to stop the fight before the final bell to advance to Friday's semifinals.

"The second round sort of killed it, it blew it to bits," Walker said, who also had no issue with Parker's exit.

Light, New Zealand's amateur heavyweight champion, advanced to a semifinal with Trieta Ruata from Kiribati when Filipe Kava was disqualified in the final round of their bout.

"It wasn't a great bout but we got a win and that's the main thing," Walker said.

Light, who was well ahead on points when the contest stopped prematurely, should be capable of reaching Sunday's final where he is likely to face Australian Jai Opetaia, a gold medallist at last year's world junior championships in Kazakhstan.

Meanwhile, the remainder of New Zealand's contingent progressed straight to the semifinals of their divisions.

Chad Milnes and Harrison Scaife were also done no favours by the draw in the 60kg and 64kg class respectively.

Cantabrian Milnes has to find a way past Tongan Lomalito Maolo, a bronze medallist at the Delhi Commonwealth Games; Scaife (Wellington) faces impressive Australian Jeffrey Horn, who won gold at the Arafura Games in 2011.

Nelson's Gage Brown has drawn Mateaki Taumalolo (Tonga) in the 56kg division while Christchurch's Bowyn Morgan (69kg) meets Nauru's Joseph Deireragea, who last boxed at the 2011 World Championships.